Endoscope

ABSTRACT

A video endoscope including an operating handle; an insertion tube extending distally from the operating handle; a camera at the distal end of the insertion tube; a working channel extending from the housing to the distal end of the insertion tube; and control cables; the operating handle including: a housing; a control lever comprising a wall and trunnions extending laterally from the wall; a first wall comprising a first support aperture; a second wall comprising a second support aperture, the first support aperture and the second support aperture receiving the trunnions to facilitate rotation of the control lever; a sealed compartment; and lateral grooves configured to receive guiding cables.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 17/204,119, filed Mar. 13, 2021 and issued as U.S. Pat. No.11,553,113 on Jan. 10, 2023, which is a continuation of U.S. patentapplication Ser. No. 16/860,831, issued as U.S. Pat. No. 10,965,844 onMar. 30, 2021, which is a continuation of U.S. patent application Ser.No. 15/576,816, issued as U.S. Pat. No. 10,645,260 on May 5, 2020, whichis a § 371 application of International Application NumberPCT/DK2016/050150, filed May 26, 2016, which claims priority fromDenmark Patent Application Number PA 2015 70319, filed May 27, 2015, allsaid applications incorporated herein by reference in their entirety.

The following applications disclose related subject matter: U.S. patentapplication Ser. No. 15/576,812, issued as U.S. Pat. No. 10,646,107 onMay 12, 2020; U.S. patent application Ser. No. 15/576,813, issued asU.S. Pat. No. 10,631,716 on Apr. 28, 2020; U.S. patent application Ser.No. 15/576,814, issued as U.S. Pat. No. 10,624,531 on Apr. 21, 2020;U.S. patent application Ser. No. 15/576,815, issued as U.S. Pat. No.10,617,284 on Apr. 14, 2020; U.S. patent application Ser. No.15/576,817, issued as U.S. Pat. No. 10,624,617 on Apr. 21, 2020; U.S.patent application Ser. No. 15/576,818, issued as U.S. Pat. No.10,779,710 on Sep. 22, 2020; and U.S. patent application Ser. No.16/839,991, issued as U.S. Pat. No. 11,337,588 on May 24, 2022; U.S.patent application Ser. No. 16/920,358, issued as U.S. Pat. No.11,478,135 on Oct. 25, 2022; and U.S. patent application Ser. No.17/931,571, filed on Sep. 13, 2022.

TECHNICAL FIELD

The present invention relates to an endoscope, in particular but notexclusively a disposable camera endoscope, having an operating handlearranged at a proximal end thereof and an insertion tube extending fromsaid handle towards a distal end of the endoscope.

BACKGROUND

In general, an endoscope comprises an operating handle at the proximalend and an insertion tube extending from the handle towards the distalend. The handle is adapted to be held by an operator and inter aliacomprises externally protruding operating members connected to internalcontrol means allowing the operator to control the motion of the distalend of the insertion tube, while advancing the distal end of theinsertion tube to a desired location e.g. within a body cavity of aperson. Examples of such endoscopes are disclosed in WO2013/071938A1 andWO2010/066789A1.

In modern endoscopes the tip forming the distal end of the insertiontube comprises a camera and illumination means allowing the operator tosee his actions on a monitor connected to the endoscope. Thisnecessitates supply and signal cables to be drawn between the tip andthe monitor. In the tip space is very limited and generally there is noor little room for electronics, such as an amplifier. The signals fromthe imaging chip of the camera may thus not be amplified at the source.Transmitting directly weak signals all the way to the monitor, isundesirable because weak signals are more prone to disturbances fromnoise picked up by long cables, than stronger signals would be.Moreover, weak signals may be prone to attenuation in connectors in thesignal path, e.g. the plug and socket connection to the monitor, andwould thus require expensive high quality connectors.

It is thus desirable to interpose amplification and signal processingmeans in the signal path from the tip of the insertion tube to themonitor, preferably at a location where more space is available, such asin the handle of the endoscope.

In the handle, however, there may in some clinical situations be a riskof undesired contact with fluids. Main problem is water, which maydisturb or ruin the electronics, in particular aqueous saline solutions,but other electrolytes may also pose problems.

It is therefore necessary to protect the electronics in a protectedmanner, sealed from such fluids.

SUMMARY

According to the present invention this object is achieved by anendoscope having an operating handle comprising a handle housingarranged at a proximal end thereof, an insertion tube extending fromsaid handle towards a distal end of the endoscope, and a sealedcompartment adapted to accommodate electronic circuitry of the endoscopeand arranged at least partially within said handle housing,characterized in that said compartment furthermore comprises a cableconduit extending from said mounting plate towards the distal end of theendoscope, said conduit being terminated in a sealing manner at thedistal end of the endoscope.

This has multiple advantages. Main advantage is that having a dedicatedsealed compartment obviates the need of sealing the outer handlehousing, which itself is difficult because the housing must allow formovable parts such as the operating buttons to protrude through thehandle housing. In particular, it provides a single sealed compartmentin which the electrical cables to the camera in the tip of the endoscopeare also protected from undesired fluids. Despite this fact, the outerhousing does provide some shielding and to some extent a two layerbarrier against influx of undesired fluids is thus provided.Furthermore, because the inner compartment is not subject to the sameergonomical constraints as the outer housing, it is much easier dodesign a joint which is easy to seal, e.g. follows straight lines, thana joint between ergonomically shaped outer housing parts. Finally,because the inner compartment is much smaller than the outer housing thejoints will be much shorter and thus easier to seal, i.e. less prone tobad gluing or welding as the case may be.

According to a preferred embodiment the sealed compartment comprises amounting plate adapted to carry said electronic circuitry, and a coverconnected to the mounting plate, so as to enclose the electroniccircuitry. The mounting plate and the cover may thereby be devised tojoin each other in a plane and may thus be designed with easily joinedstraight lines.

According to a further preferred embodiment, the operating handlecomprises a shell structure. Using a shell structure with several shellparts facilitates the assembly of the endoscope, and in particularaccess to inner components in the handle when mounting them.

According to a further preferred embodiment, the operating handlecomprises an inner, essentially shell shaped chassis having a shellstructure with a shell wall with an inner surface and an outer surfacelinked by an edge, said shell structure defining an interior compartmentdelimited by said inner surface and the edge of the shell wall, the edgethus defining main opening of said interior compartment, and in that themounting plate is adapted to engage said shell shaped chassis in thevicinity of the edge, so as to partially cover said inner compartment.In this way the mounting plate may be used to stabilize and increase therigidity of the shell shaped chassis, in turn allowing the shell shapedchassis to be weakened by apertures provided in the wall and or by theuse of a further reduced wall thickness, be it localised or overall.

According, to another preferred embodiment the mounting plate comprisesa number of flanges adapted to extend into the interior compartment whenthe mounting plate is in engagement with said chassis and partiallycovers the inner compartment. Providing such flanges allow theseparation between inner parts. In particular movable ones, such ascontrol cables, may be kept separate from other parts which may be proneto damage from the moving cables.

According to a further preferred embodiment, the cable conduit isaccommodated within an outer sheath of the insertion tube. Therebyadditional protecting against undesired fluids is provided.

According to yet another preferred embodiment, at least one of saidmounting plate or said cover is made from a transparent plasticmaterial. If one, or preferably both of said mounting plate and saidcover is made from transparent material, the two parts may efficientlybe sealed along the joint by the use of UV curing glue or resin.Likewise applies to the joining of the mounting plate to the chassis ifdesired.

A person skilled in the art will appreciate that any one or more of theabove aspects of this disclosure and embodiments thereof may be combinedwith any one or more of the other aspects of this disclosure andembodiments thereof.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will now be described in greater detail based onnon-limiting exemplary embodiments and with reference to the drawings,on which:

FIG. 1 shows an exploded overview of an endoscope according to thepresent invention and how this exploded view is split in a left-handside part and a right-hand side part for better visibility in FIG. 1 aand FIG. 1 b,

FIG. 2 shows a perspective view of the fully assembled endoscope of FIG.1 ,

FIG. 3 shows a monitoring device adapted for mutual connection with theendoscope of FIG. 1 ,

FIG. 4 shows a first perspective view of a chassis of the endoscope ofFIG. 1 ,

FIG. 5 shows a second perspective view of the chassis of FIG. 4 ,

FIG. 6 shows a third perspective view of the chassis of FIG. 4 ,

FIG. 7 shows a perspective view of the chassis of FIG. 4 with controlcables and a control member mounted,

FIG. 8 shows a semi-assembled endoscope according to the invention withthe chassis, movable parts and a housing shell part,

FIG. 9 shows a top perspective view of a mounting plate for carryingelectronics of the endoscope,

FIG. 10 shows the mounting plate carrying the electronics of theendoscope with electrical wiring extending therefrom,

FIG. 11 shows bottom perspective view of a cover adapted to fit themounting plate of FIG. 9 ,

FIG. 12 shows a top perspective view of an assembly of the mountingplate of FIG. 9 and the cover of FIG. 11 , and

FIG. 13 shows a bottom perspective view of the assembly of FIG. 12 .

DETAILED DESCRIPTION

Turning first to FIG. 2 an assembled endoscope 1 according to thepresent invention is shown. The endoscope 1 has a proximal end with anoperating handle 2 to be held in one hand by an operator. Accordingly,the operating handle is shaped in a manner ergonomically suitable foroperator, in particular but not exclusively for the hand of theoperator, as arms and joints may also play a role in the ergonomics.From the handle 2 an insertion tube 3 extends towards the distal end ofthe endoscope. At the distal end of the endoscope 1 the insertion tube 3ends in a bending section 4 and a tip part 5. The bending section 4 isin mechanical connection with an operating member 6, digitally operableby the operator, e.g. by the thumb, thereby allowing the operator tobend the tip part 5 in a desired direction when advancing the insertiontube 3 towards a desired location, e.g. through a body cavity of apatient. As can also be seen the endoscope 1 comprises a flexibleconnection cable 7 with a connector 8 allowing the endoscope 1 to beconnected to a monitoring device such as a monitor 92 shown in FIG. 3forming part of an endoscope 1 and monitor 92 system.

Turning now to FIGS. 1, 1 a and 1 b, an exploded view of the endoscope 1is shown. As mentioned, the endoscope 1 has an operating handle 2 at theproximal end thereof i.e. at the left-hand side of FIG. 1 a . Theoperating handle 2 is assembled from and comprises a number of handleparts to be described later. From the operating handle 1, the insertiontube 3 comprising a number of insertion tube parts to be described laterextends towards the distal end of the endoscope, i.e. towards theright-hand side of FIG. 1 b.

As can be seen in FIG. 1 a , the operating handle 2 comprises at leasttwo shell parts 9, 10 forming the outer housing walls of the handlehousing of the operating handle 2. The two shell parts 9, 10 form theouter housing walls and are shaped to provide an ergonomically suitableoperating handle for an operator, gripping it with one hand. In additionto the two shell parts 9, 10 a transition part 11 forming the transitionfrom the operating handle to the insertion tube 3, may be provided. Thistransition part may also form part of the handle housing. However, thetwo shell parts 9, 10 constitute the major part of the housing in theembodiment shown.

The two shell parts 9, 10 are adapted to engage and be held and besupported by a chassis 12, in turn, adapted to support said at least twoshells parts 9, 10 by suitable engagement means, such as recesses and/orprotrusions 13 interlocking with suitable complementary means 14, 15 onthe chassis 12, better visible in FIGS. 4 and 5 . Furthermore the shellpart 10 has pair of columns 88 of which only one is visible in FIG. 1 a. These columns 88 serve the attachment of the shell part 10 to thechassis 12. The shell part has internal engagement means (not visible)adapted to engage the shell part 9 at the proximal end of the endoscope1, so as hold them together. At the other end the shell parts are heldtogether by the transition part 11.

Turning now to the FIGS. 4, 5 and 6 , the chassis 12 will be describedin greater detail. The chassis 12 preferably shell shaped, i.e. saidchassis comprises an essentially shell shaped structure with a shellwall having an inner surface 16 and an outer surface 17 linked by anedge 18, said essentially shell shaped structure defining an interiorcompartment 19 delimited by said inner surface 16 and the edge 18 of theshell wall, the edge thus defining main opening 20 of said interiorcompartment 19. It will be understood that the chassis 12 can bedesigned mainly based on technical requirements, such as kinematicchains of movable parts, and thus be optimized for those technicalrequirements without having to inherit constraints from the ergonomicrequirements of the handle 2, i.e. the shape of the two shell parts 9,10.

Best visible in FIGS. 4 and 5 are a number of different apertures andcut-outs formed in the chassis 12. These apertures form vias fordifferent purposes between the interior compartment 19 and the exteriorof the chassis 12.

The different cut-outs and apertures differ in shape, size, location andlayout depending on their purposes, and may as mentioned be designedaccording to technical requirements, independently of the ergonomicrequirements of the handle 2.

Starting from the proximal end of the endoscope 1 there is an aperture21, as best seen in FIG. 6 . The aperture 21 accommodates a push button22, so that the push-button 22 extends from the interior compartment ofthe chassis 12 to the exterior, and on through an aperture in the shellpart 9 to be accessible by an operator holding the handle 2 of theendoscope 1. The push-button 22 is preferably biased towards an externalposition by means of two coil springs 83 guided by two guiding columns84 fixed in the bottom two wells provided in the chassis 12, preferablyby gluing using UV-curable glue or resin transmitted through thetransparent material of the chassis 12. The two guiding columns 83further serve to reduce friction between the coil springs 83 and thecolumns 88. They are therefore preferably made of a material withrelatively low friction, such as low-density polyethylene LDPE, e.g.Comothene® 4812.

On the outer surface 17 of the shell wall of the chassis 12 two lugswith holes 89 are provided. These serve to engage the columns 88 on theshell part 10 for attaching it to the chassis, as described above.

In the shell wall two elongate apertures 23 in the form of slits areprovided. The two elongate apertures 23 are preferably arranged as apair, one on either side of the aperture 23. The two elongate apertures23 serve as guide means for the push-button by accommodating arespective protrusion 24 provided on the surface of the push-button 22.

In the vicinity of the two elongate apertures 23, a first and a secondpair of apertures 25, 26 in the form of essentially cylindrical throughholes are provided. The first pair of essentially cylindrical aperturesserve as pivotal bearings for trunnions 27 of a control lever 28 formaneuvering the bending section 5 via a pair of Bowden pulls 29. As canbest be seen in FIGS. 1 and 2 , the control lever 28 is attached to thecontrol knob 6, and at least the control knob extends to the outside ofthe endoscope handle 2 through a slit 30 in the shell part 10 to beaccessible by a thumb of the an operator. It should be noted that it isnot essential for the function as bearings for the trunnions 27 of thecontrol knob, that the holes are though holes, but because the chassisis preferably injection moulded, through holes may be much easiermanufactured than e.g. blind holes.

It will be understood that due to the slit 30 and other necessaryopenings in the shell parts 9, 10, the handle housing does not protectthe internal components fully. Though some protection against spray andsplash is provided by the shell parts 9, 10 there is basically fluidcommunication between the exterior and the interior of the handlehousing. This is largely intended, as sealing these openings would beunnecessarily complicated and costly.

The second pair of apertures 26 are preferably also circular throughholes and have the same diameter. They need not be circular, however, astheir purpose is allowing the insertion of a tool, such as a rod inorder to immobilise the control lever 28 during assembly of theendoscope, more specifically when attaching the proximal ends of thecables 31 of the two Bowden pulls 29 to the control lever 28.Accordingly, the control lever 28 has a through hole 32, correspondingin size to the apertures 26, and adapted to align with these in oneposition of the control lever 28, thereby allowing the insertion of thetool through all three holes, 26, 32, so as to block movement of thecontrol lever 28 with respect to the chassis 12. The position of thethree holes 26, 32 are selected so as to block the control lever 28 in aposition later corresponding to a neutral position of the control lever28 and knob 6, in which the bending section 4 is straight.

With the control lever 28 blocked during assembly the cables 31 Bowdenpull may be attached to the control lever 28 in a well defined manner.This is preferably done by threading the respective free end of eachcable 31 through suitable passages in the control lever 28, forming aloop 43 by looping the free ends back to the respective cable andcrimping the free end onto the cable 31 using a barrel 33. The barrel 33may be of the open barrel type, to avoid the hazel of sliding the barrel33 on onto the cable 31 prior to crimping. Evidently, other attachmentsfor the loop 43, such as protrusions, may also be used. Furthermore,entirely different attachments methods without loops are also envisaged,albeit not preferred.

To facilitate this assembly process a cross-shaped aperture 34 islocated in the vicinity of the bottom of the chassis 12, i.e. away fromthe main opening 20 defined by the edge 18. Likewise a cut-out 35 in thewall from the edge 18 is provided. The cross-shaped aperture 34 and thecut-out 35 allows access to the cables 31 various tools, such as holdingand crimping tools during the assembly.

As can best be seen in FIG. 5 the cross-shaped aperture 34 a further,essentially rectangular aperture is generally aligned with a furtherrectangular access aperture 36 and a pentagonal aperture 37 in thedirection towards the proximal end of the endoscope 1. The cross-shapedaperture 34, the rectangular aperture 36 and the pentagonal aperture 37are separated by respective bridges 38 and 39. These bridges 38, 39 donot follow the general curvature of the outer surface 17 of the chassis12 but are indented to form a generally V-shaped groove 40 connectingthe cross-shaped aperture 34 to the pentagonal aperture 37 via therectangular aperture 36. As can be seen from FIG. 7 , this V-shapedgroove 40 in the outer surface 17 provides the outer surface 17 with ameans for guiding one or more movable parts, in particular the cable 31of the Bowden pull between two apertures, such as the cross-shapedaperture 34 and the pentagonal aperture 37 along the outer surface 17outside of the interior compartment 19. This in turn allows theunsupported free end of the cable 31 of the Bowden pull to follow astraight line. At the same time, because the unsupported free end of thecable 31 passes from the interior compartment 19 of the chassis 12 tothe exterior via the cross-shaped aperture 34, the cable 31 becomeseasily accessible for the assembly tools, in particular the crimpingtool. The cross-shape of the cross-shaped aperture, in turn, facilitatesthe use of the tools by providing the necessary space for opening andclosing the tools, be it a crimping tool or a holding tool.

In FIGS. 4 and 5 a further pair apertures 41 in the form of essentiallycylindrical through holes can be seen. Similar to the apertures 25, thefurther pair of apertures 41 serve as bearings of trunnions 42 carryinga pinion 44. The pinion 44 is adapted to be in engagement with a curvedrack 45 having a first free end 46 and a second end with trunnions 47held loosely in suitable receptacles inside the push button 22. The rack45 as such is loosely held in a guideway comprising a first side 85, asecond side 86 and a curved bottom 87 adapted to keep the rack 45 inengagement with the pinion 44, cf. FIG. 6 . The first side 85 and thesecond side 86 as well as the curved bottom 87 are preferably formedintegrally with the remainder of the chassis 12, e.g. in an injectionmoulding process. The first side is preferably constituted by a planesurface of a thickened part of the wall, i.e. a raised part of the innersurface 16 of the chassis 12.

Rotation of the pinion 44 may be effected by an operator moving thepush-button 22, e.g. depressing it using an index finger, upon which thepush-button transfers motion to the curved rack, in turn rotating thepinion 44.

On the pinion 44, two lever arms 48 and 49 of different lengths areprovided. These arms 48 and 49 are in rigid connection with the pinion44. Via a number of intermediate parts 50, 51, 52, 53 and 54 a desiredoperation of a tool 55 at the tip part 4 at the distal end of theendoscope 1 may be effected when the pinion 44 is rotated. The manner inwhich the operation of the tool 55 is to be effected may depend on thedetails of the tool. Variations in requirements can be controlled independence on the differences in lengths of the lever arms 48 and 49,and possibly articulations of the intermediate part 50, at the designstage of the endoscope 1 with a tool for a specific purpose.

As can best be seen in FIGS. 4 and 6 a number of apertures 56 arearranged to form openings from shelves 57 on the inner surface 16 of thechassis 12 to the outer surface 17 of the chassis 12. These openings areadapted to form undercut receptacles for protruding barbs 58 on amounting plate 59 best seen in FIGS. 9, 10 and 13 . The mounting plate59 is preferably injection moulded from the same transparent plasticmaterial as the chassis 12. Using a transparent plastic material isadvantageous in that it allows parts to be joined and/or sealed using anUV curable glue or resin, i.e. one that hardens under the influence ofultraviolet light. In respect of glue or resin, be it UV curable or not,it has been found that simply gluing the proximal end portions of theouter tubes 60 of the Bowden pulls 29 in suitable recesses 61 providedalong the inner surface 16 of the shell wall is sufficient to secure theBowden pulls 29 in position. This is primarily, because, as it has beenrealized, adjustment is not needed. Adjustment, in turn, is notnecessary because any slacking of the pull cable 31 of the Bowden pull29 is negligible in a disposable endoscope 1. The pull cables 31 are notunder any substantial tension during shelf life and will hardly undergoany mentionable stretching during the one short occasion the disposableendoscope 1 is in use.

The mounting plate 59 when attached to the chassis 12, and possiblysecured thereto by preferably UC curing resin or glue, forms a partiallid over the main opening 20, and hence partially encloses the interiorcompartment 19. Closing the interior compartment partially on all foursides, rather than only three, adds rigidity to the chassis 12 as ithinders lateral compression, i.e. of the shell walls towards each other.Accordingly, the chassis 12 and in particular the walls parts thereofmay be made with a reduced strength, i.e. thinner or with more or largerapertures than would otherwise be possible.

As the name suggest, the reinforcing of the chassis 12 it not the mainpurpose of the mounting plate 59. Rather, the mounting plate 59 isadapted to carry electronic circuitry of the endoscope 1, e.g. on aprinted circuit board 62, as can best be seen in FIG. 10 . In thefollowing the electronic circuitry on the printed circuit board 62 willbe referred to as main electronics. This is mainly to distinguish fromother electronics located at or embedded in the tip 4 of the insertiontube 3 of the endoscope 1 which will accordingly be termed tipelectronics. Both for the term main electronics and the term tipelectronics it should be borne in mind that this description relates toa non-limiting exemplary embodiment, and that no functionalityrequirements should be attributed to these terms.

In modern camera endoscopes 1 the tip part 4 forming the distal end ofthe insertion tube 3 comprises a camera, such as a CCD camera, andillumination means, such as an LED, allowing the operator to see hisactions on a monitor 92 connected to the endoscope 1. This necessitatessupply and signal cables or wires 7, 63 to be drawn between the tip part4 and the monitor 92. In the tip part 4 space is very limited and apartfrom the camera and illumination means there no or little room forelectronics, such as an amplifier. The signals from the imaging chip ofthe camera may thus not be amplified at the source. Therefore the weakelectrical analogue signals from the camera which are prone todisturbance by electrical noise picked up by signal wires, cables etc.on the way to the monitor 92. To overcome this, the main electronicsacts as an intermediate between the tip electronics electrical powersupply and amplification. Thus the weak signals from the camera arrivingon the wires 63 may be amplified and otherwise modified, e.g. digitallyencoded before they are transmitted to the monitor 92 via the flexibleexternal connection cable 7. The present invention thus takes advantageof the fact that in the handle 2 of the endoscope 1 there is much betterroom for the amplification and signal processing means than anywhereelse in the signal path from the tip part 4 at the distal end of theinsertion tube 3 to the monitor 92.

Furthermore, with the main electronics being located on the mountingplate 59 in conjunction with the chassis 12 it becomes possible toaccommodate the electronics according to technical requirements, withoutmuch consideration to ergonomic properties and the general layout of thehandle 2. One particular technical requirement is the protection of theelectronics against undesired contact with fluids such as water, whichmay disturb or ruin the electronics, in particular aqueous salinesolutions. Other electrolytes may also pose problems, but main problemis water which in many clinical situations is ubiquitous. Thetraditional approach in multiple-use endoscopes as well as in singleuse, i.e. disposable endoscopes 1 has been to seal the outer housing.This, however, is difficult and costly because the integrity of thehousing needs to be breached in order to allow the passage of movableoperating parts, such as in the endoscope 1 according to the presentinvention the push-button 22 and the control button 6.

Accordingly, the present invention realizes that by fitting a suitablecover 64 a sealed compartment for the main electronics may be providedwithin the handle, thus obviating the need for sealing the outer housingof the handle 2. The skilled person will understand that this applies,not only to the operating handle with a chassis 12 on which thepreferred embodiments are based, but to operating handles for endoscopesin general. Thus the mounting plate 59 could also be mounted anddirectly within a shell part of an operating handle without a chassis12, thereby protecting the main electronics, and possibly reinforcingthe shell part mechanically.

The cover 64 has an edge 65 which essentially lies in a single planeexcept for a passage 66 for the cables 7, 63 to enter and exit thecompartment. The edge 65 is thus adapted to engage a plane surface ofthe mounting plate 59 in close vicinity of the edge 68 of the mountingplate 59. As can be seen the edge 68 is preferably raised along thecircumference of the mounting plate thus facilitating the positioning,attaching and sealing of the cover 64 with respect to the mounting plate59. This attaching and sealing of the cover 64 with respect to themounting plate 59 is preferably also performed using UV curable glue orresin, and accordingly the cover 64 is therefore also made oftransparent plastic material, e.g. injection moulded like the chassis 12and mounting plate 59. The chassis 12, mounting plate 59 and the cover64 are preferably all made of the same material, thus facilitating thechoice of a glue or resin with suitable adhesive and cohesiveproperties. This glue or resin may also be used to seal directly aroundthe cable 7 and wires 63 at the passage 66. Preferably, the mountingplate 59 has a receptacle 69 in the shape of a half-pipe, serving toreceive and hold the cable 7 and wires 63 as well as serve to limit theamount of UV curable glue or resin used when sealing the compartmentaround the cable 7 and wires 63.

In a preferred embodiment, however, the glue or resin does not sealdirectly around the cable 7 and wires 63. Instead the wires 63 are drawnfrom the compartment to the tip part 4 of the insertion tube 3 of theendoscope 1 within a wire or cable conduit 70, seen only in FIG. 1 .Consequently, the sealing at the passage 66 will be around the conduit70 and the cable 7. The conduit 70, in turn, is sealed at the tip part 4at the distal end of the insertion tube 3 of the endoscope 1, therebyproviding a sealed compartment extending all the way to the tip part 4,where it is preferably moulded in together with the camera housing. Thissealed compartment protects the wires 63, which are relatively thin,against mechanical stress while preserving the sealing properties.

On the opposite side of the mounting plate 59 away from the compartmentand the printed circuit board 62, two perpendicular flanges 77 areprovided. These confer additional rigidity to the mounting plate 59 buttheir main purpose is to serve as protective barriers for a flexiblehose 71 of a working channel of the endoscope 1. Like many prior artendoscopes, the endoscope 1 of the present invention comprises a workingchannel e.g. allowing liquid or fluid to be delivered to or extractedfrom the body cavity into which the endoscope has been advanced.

Starting from the distal end of the insertion tube 3 of the workingchannel as a first tube segment 72 attached to and preferably embeddedin the tip part 4 at one end. The second end of the first tube segment72 is connected to a first end of a second tube segment 73 by means of ashort length of rigid tubing 74. Rigid in this sense is to mean morerigid than the second tube segment 73 which, in turn, is more rigid thanthe first tube segment 72 which has to comply with the flexibilityrequirements of the bending section 5. Similarly, the first tube segment72 is more rigid than the flexible hose 71. In this respect it ispreferred to make the flexible hose 71 of a first polyurethane elastomerand to make the first tube 72 of another polyurethane elastomer. Bothpolyurethane elastomers could be Pellethane®, which is available indifferent variants. The second tube segment 73 may also comprisepolyurethane. The second end of the second tube segment 73 is connectedto a T-joint 75 in connection with a connector 76 or lead-in mounted onchassis 12 in connection with a circular aperture 91 and serving toconnect a hose of a suction or irrigation means to the working channelso as to extract or deliver aforesaid liquid or fluid to the body cavityinto which the endoscope has been advanced.

However, in the endoscope 1 according to the present invention theworking channel serves not only fluids or liquids, but also serves as aworking channel for the tool 55, which means that a sealing is necessarywhere the motion of the lever arms 48 and 49 are transferred to themovable intermediate parts 53 and 54 which are largely accommodatedwithin the first tube 72 and the second tube 73 of the working channel.This sealing is achieved by the use of the flexible hose 71 which isfixed at one end at the intermediate part 51 and at the other end at theT-shaped joint 75. The hose 71 may have a smooth surface in a relaxedstate or it could be corrugated to form a bellows. The hose 71 is of ahighly flexible thin-walled material as compared to the first tube 72and the second tube 73 of the working channel, because it has to be ableto comply with the relative motions between the intermediate parts 50,51, 52 which is a compound translatory and rotational movement in twodimensions with respect to the chassis 12.

This compound translatory and rotational movement in two dimensions withrespect to the chassis 12 make the hose 71 prone to damage from othermovable parts of the endoscope 1. This is in particular the case for thecables 31 of the Bowden pulls 29 and certainly the crimps 33 even thoughsome protection is achieved by guiding the cables 31 outside of thechassis 12 in the V-shaped grooves 40. As mentioned above, thisprotection is further increased by at least one of the flanges 77.

This compound translatory and rotational movement in two dimensions withrespect to the chassis 12 is quite substantial, and to accommodate forthe movement of the intermediate part 50 in one direction therectangular aperture 36 is provided in the wall of the chassis 12. Inthe other direction the bottom 78 of the mounting plate between theflanges 77 serves as a strike plate to limit motion of the intermediatepart 50 so as to be abutted by the claw like end 79 thereof which clampsand holds the intermediate member 52 inside the hose 71. This limitationof the motion prevents the section of the hose 71 located between theclaw like end 79 and the intermediate part 51 to which the hose 71 isattached to be overstretched and rupture. The flanges 77 serve also toguide and control the movements of the hose 71 and claw like end 79, inparticular in the lateral direction.

The entire insertion tube 3 is sealingly encapsulated in a flexibleouter tube. The outer tube comprises a first outer tube section 80 and asecond outer tube section 81 joined with a sleeve 82. Similarly to theworking channel the first outer tube section 80 is more flexible thanthe second tube section 81 in order to comply with the movements of thebending section 5. The second tubular member 73 is however still quiteflexible. More specifically, the second tubular member 73 and a secondouter tube section 81 surrounding it are so flexible that they allow aloose knot to be tied on the insertion tube 3. The alternative is arigid or semi-rigid endoscope where the insertion portion is rigid, onlyslightly bendable or hinged, and which does not allow a knot to be tiedon the insertion tube. Preferably, the first outer tube section 80 ismade from the very same material as the hose 71, either of them simplycut to a suitable length from a stock of tubular material for therespective purpose.

Returning now to FIG. 1 a, a protective tubular member 90 can be seen.The intermediate part 11 has a slightly frustoconical section adapted toreceive one end of the protective tubular member 90. The protectivetubular member does not form part of the endoscope 1 as such but servesas a protective means during storage.

What is claimed is: 1-8. (canceled)
 9. An endoscope comprising: anoperating handle comprising a housing having an inner surface and aninner compartment; an insertion tube extending distally from the housingand having a distal end; a camera at the distal end of the insertiontube; a working channel extending from the housing to the distal end ofthe insertion tube; and control cables; a control lever comprising awall and trunnions extending laterally from the wall; a first wallcomprising a first support bearing; a second wall comprising a secondsupport bearing, the first support bearing and the second supportbearing receiving the trunnions to facilitate rotation of the controllever; and a sealed compartment in the inner compartment; electroniccircuitry enclosed in the sealed compartment; and grooves configured tosupport the control cables in the inner compartment.
 10. The endoscopeof claim 9, wherein the sealed compartment comprises a mounting plateand a cover connected to the mounting plate.
 11. The endoscope of claim10, wherein the mounting plate is configured to carry said electroniccircuitry.
 12. The endoscope of claim 9, wherein the first supportbearing and the second support bearing comprise, respectively, first andsecond apertures.
 13. The video endoscope of claim 9, wherein the firstwall comprises a control lever immobilization aperture configured toreceive a tool and thereby immobilize the control lever in a neutralposition during attachment of the control cables to the control lever.14. The video endoscope of claim 9, wherein the first wall comprises acontrol lever immobilization aperture configured to receive a tool andthereby immobilize the control lever in a neutral position duringattachment of the control cables to the control lever.
 15. The videoendoscope of claim 9, further comprising a shell structure having anouter surface and an inner surface and being positioned in the housingwith the outer surface facing the inner surface of the housing, theshell structure comprising the first wall and the second wall.
 16. Thevideo endoscope of claim 15, wherein the shell structure comprises thegrooves, and wherein the grooves are configured to support the controlcables between the outer surface of the shell structure and the innersurface of the housing.
 17. The video endoscope of claim 15, wherein theshell structure comprises a cross-shaped aperture establishing fluidcommunication between the inner surface and the outer surface thereof,the cross-shaped aperture providing access from the outer surface to theinner compartment to facilitate assembly of the endoscope.
 18. The videoendoscope of claim 15, wherein the shell structure comprises across-shaped aperture and a rectangular aperture separated from thecross-shaped aperture by a bridge, one of the grooves formed by thebridge.
 19. The video endoscope of claim 9, wherein the sealedcompartment comprises a mounting plate and a cover connected to themounting plate, the endoscope further comprising a structure comprisingthe first wall, the second wall, the mounting plate and the grooves,wherein the mounting plate is configured to carry said electroniccircuitry, and wherein the first support bearing and the second supportbearing comprise, respectively, first and second apertures.
 20. Thevideo endoscope of claim 19, wherein the structure further comprises across-shaped aperture and a rectangular aperture separated from thecross-shaped aperture by a bridge, one of the grooves formed by thebridge.